Hydraulic reversing check valve



Jan. 10, 1950 I F. ,1. WRIGHT HYDRAULIC REVERSING CHECK VALVE Filed May 16, 1944 INVENTOR FEED J. WQIGHT.

Patented Jan. 10, 1950 HYDRAULIC REVERSING CHECK VALVE Fred J. Wright, Upper Arlington, Ohio, assignor,

by mesne assignments, to The Jeffrey Manufacturing Company, a corporation of Ohio Application May 16, 1944, Serial No. 535,806

2 Claims.

This invention relates to a reversing check valve for a hydraulic system and an object of the invention is to provide such a device in which there are a minimum of parts requiring accurate machining, the wearing parts are readily replaced, and the parts are so constructed and arranged that they may be readily assembled and disassembled.

Other objects of the invention will appear hereinafter the novel features and combinations being set .forth in the appended claims.

4 In the accompanying drawings,

1 Fig. l is a schematic piping diagram of part of a hydraulic system showing the function of the reversing check valve of my invention;

Fig. 2 is an elevational end view of the check valve of my invention; and

Fig. 3 is a transverse sectional elevational view of said check valve.

In certain hydraulic systems a pump is provided which may be reversely operated by the drive motor yet it is necessary that pressure always be supplied to a pressure conduit of the hydraulic system. The function of the reversing check valve of my invention is to make this possible.

. In Fig. 1 of the drawings a portion of such a system is shown in which there is a tank III for the hydraulic fluid. A feed pipe or conduit II leads from the tank III to the reversing check valve designated generally by the reference character I2 which is illustrated diagrammatically in Fig. 1 of the drawings and disclosed in detail in Figs. 2 and 3 of the drawings. The reversing check valve I 2 is in eiiect four check valves. Connected to the reversing check valve I2 is a pair of conduits or pipes I3 and I4 leading to a reversible pump I5. Also extending from the reversing check valve I2 is a pressure conduit I6 by which hydraulic pressure is conducted to any desired system. As previously mentioned, regardless of the direction of rotation of the pump I5, hydraulic fluid under pressure will always be present in conduit I6. Conduits I3 and I4 will either be suction or pressure conduits leading to the pump I5, depending on its direction of rotation.

v In Fig. 1 of the drawings there is also illustrated a leakage return conduit I'I leading from the pump I to the tank III.

Referring particularly to Figs. 2 and 3 of the drawings, the reversing check valve I2 includes a main body or casting I8 provided with a pair of laterally spaced equal diameter boresv I9 and which are of uniform diameter throughout and extend completely through the casting or 2 body I8 from the top to the bottom. Adjacent the tops of bores I9 and 20 and communicating therewith are chambers 2| and 22 communicating with bores I9 and 20, respectively. Said chambers 2| and 22 are interconnected by a passageway or conduit 23 formed in the central portion of the body I8, which passageway 23 communicates with pressure pipe I6 which is threaded or otherwise attached to a threaded opening in a head or end plate 24 attached to the top of the casting I8 as by machine screws 25 (see Fig. 2). A compression gasket 26 provides a seal between the upwardly extending or main portion of passageway or conduit 23 and the threaded bore in end plate 24. Also adjacent the bore I9 and below the chamber 2| is another chamber 21 which communicates with said bore I9 and which leads by way of a port in said casting I8 to the conduit or pipe I3. Likewise there is a chamber 28 adjacent the bore 20 and in communication therewith which is in lateral alignment with the chamber 21 and thus positioned below the chamber 22. Chamber 28 communicates by way of a port in casting I8 with the pipe I4. As previously mentioned, the internal metal surface provided by the two equal diameter bores I9 and 20 is uniform substantially throughout its length so that they can both be formed by the simple expedient of drilling a uniform bore through the casting I8. In construction of the device these two holes may be drilled simultaneously.

- Adjacent their tops the bores l9 and 20 are provided with enlarged grooves for receiving the receiving rings 29 and 30 which effect a -seal between the tops of said bores and the head orend plate 24. These ends of the bores l9 and 20 are the high pressure ends and are connected to the high pressure conduit I6. Communicating with the bottoms of the two bores I9 and 20 is a feed passageway 3I formed in a bottom or end plate 32 which is attached to casting I8 by screws 33. End plate 32 has a threaded opening which threadedly receives the feed pipe I I. Within each of the bores I9 and 20 there is what in efiect constitutes a pair of check valves, one associated with each of the four chambers 2I, 22, 21 and 28. Each of said check valves is built up by three principal parts, the principal parts of each being identical with the other. For example, associated with chamber 2| there is a cylindrical spacer sleeve 34, a cylindrical seat ring35 and a ball 36. Similar parts. of the individual check valve associated with chamber 22 are designated I34, I35 and I36. Likewise similar parts associated with chamber 21 are designated 234, 235 and 233 3 and similar parts associated with the chamber 28 are designated 334, 335 and 336. It is thus evident that the three principal parts of each of the four check valves are interchangeable. This results in great saving in manufacture as well as the replaceability of worn parts.

In the assembly of the four individual check valves it. isonly'necessary to remove: one of .the end plates 24' or 32 and slide the sleeves 34, I34, 234 and 334 and the seat rings 35, I35, 235 and 335 in place, the parts being assembled by alternately inserting a spacer sleeve, then aseat ring, or vice versa, depending upon which end plate is removed, and placing a ball within each spacer sleeve. To provide a seal between eachseat ring; 35, I35, 235 and 335, the external cylindrical surface thereof is provided Witha-groove inwhich" a rubber seal ring is placed, that with ring 35 being designated 31, there being similar seal" rings I31, 231 and 331 for the seat rings I35, 235 and 335-, respectively.

The spacer sleeves 34, I34, 234-and 334 are'provideef with four radial holes 38, I38, 238- and338, respectively, which provide free communication between. the interior of the spacer sleeves and their adEiac'entchambers 2|, 22, 21 and 28, re-- spectively.

It'is obvious that all of the spacer sleeves 34, 34 ,234- and 334-and the seat rings 35, I35, 235 and 335: are generally cylindrical in structure and epen at both ends. Furthermore, the external' diamet'ers of all of" them are substantially equal'and they have-a fairly close fit with-the internalcylindrical surfaces of the bores I5 and 2|! with which they are associated. It is to be noted that: the stacked spacer sleeves and seat-ringsin the bores I 9 and -2il have sucha total dimension longitudinaliyor axially of the bores I9 and that thereisa slight clearance between the top spacer sleeves I'Earrd' I3 and the head or end plate 24. As a consequence, relative movement between each 01 the spacer sleeves and seat rings and the side wal's' of bores I 9 and 26 is provided. In other words, there is no attempt made-to fit the spacer sleevesand seat rings to the exact longitudinal dimensions of the bores-I3 and2'0', thus-exact Ina-- chiming and dimensioning of the axial lengths of spacer sleeves 34, I 34, 234 and 334 and seat'rings 35 I35; 235 and 335 are not required.

The seat rings 35, I35, 235- and 3 35 and'the' cooperating balls 36, I35, 236' and 336*willbe" hardened to increase the life thereof since they are the wearing parts which actually provide the individuar check valves involved. These parts, o'f course, can-be individually hardened and'therefore they arethe only parts'of' the complete revers'ing check valve Ir'Z- that need this special treatment; Furthermore, seat rings 35, I35, 235' and 335-' ii worn, maybe reversed to'present new seating surfaces.

Ih theoperation of the device, the pump I5 will be rotated in one direction and it will be presumed that it is rotating so that pipe I3 is an inlet pipe and pipe '[4' a discharge pipe. Under such conditions hydraulic'fluid will be-drawn'from the tank Iflbyway ofpipe I I' through passageway 3 1 and through the check valve provided-by ball 236 and seat ring 235, in which case the ball 236 will-belifted to break the seal. Hydraulic fluidwill flow through radial openings 238 in spacer s1'eeve 234 into chamber 21, thence to pipe I3 andpump I 5. Hydraulic fluid under presure'will from pump I5 through pipe I4 to chamber 28; and into sleeve 334 by way of radial holes 338. This pressure insleeve 334 will causetheba'll' 335' 4 to seat on the seat ring 335, closing this individual check valve. The hydraulic fluid under pressure in sleeve 334 will flow upwardly in the cylindrical opening in ring I35 and lift the ball I36, thus flowing into sleeve I34 and through radial openings I38 thereof into chamber 22 and thence by way of passageway 23 to the pressure conduit or pipe IG' which this hydraulic fluid is then delivered to the rest of the hydraulic system. The hydraulic fluid under pressure in passageway '23 causes pressure within the sleeve 34, which communicates therewith through radial holes 38,

thus seating the ball 36 on its associated seat ring hould the-pump I5 be reversed, the conduit I3 will be the output conduit and the conduit I4 will-be. theinput. conduit thereto and under these conditions hydraulic fluid from feed pipe II will flow upwardly through check valve 335-336 to conduit I4 and to pump I5, thence from pump I5 byway of conduit I3 and through obvious chambers, hores and-passageways to check valve 35-'36 and then topressureconduit I6. The hydraulic fluid under pressure under these conditions will? sealthe'check valves I35-I35 and 2352-36*. The operation under these conditions is believed obvious from the brief description above given, th gether with the detailed description previouslyg'iven of the-reverse operationof said pump-I5.

To'reiterate briefly, it is to be noted that each" of the bores I9 and 20' is provided with two check valves, the four check valves each being formed of" three principal parts which are of identical construction for each valve and thus each-"part" is interchangeable or usable in any check valve. These three parts are thespacer sleeves 34', I34, 234 and 334, the seat rings 35, H5 235 and 335 and balls 36', I36, 236' and 355. Also there are two spacer sleeves and two seat rings in' each bore I-9- and--20, said spacersleeves and seat rings being stacked alternately one on top of the other in each' bore I9 and 2!] and being free to move a limited amount longitudinally therein after the end plates 2'4 and 32' areattached;

Qbviously those skilled inthe -art may make various changes in the details and arrangement" of parts without" departing from" the spirit and scope of the invention as defined by the claims hereto appended, and I therefore wish not to be restricted to the precise construction herein disclosed.

Having thus described an embodiment of invention, what I desire to secure by LettersPatentof' the United States is:

l. A check valve including a main body, having a bore, removable end plates attached tosaidf body'- extending over said bore, a cylindrical spacer sleeve insaid bore, a separate se'at'ring in said'bore, said spacer sleeve and seat ring having: outside diameters to fit into said bore and having abutting contact while being free from positive connection toeach other, said end plates co-opcrating, to hold said' spacer sleeve and seat ring in said bore, and a ball in said spacer'sleeve 00- operating with said seat ring to provide a check seal.

'2. A check valve including .a' main body, having a bore, removable'en'd'plates attached to" said body extending, over saidborea cylindricaispacer sleeve in said bore, a separate seat ring in said bore, said spacer sleeve and seat ring: having outside. diameters to fit into said bore and having abutting contact while being free from positive connection to each other, said end plates c0-operating' to hold said spacer sleeve and seat-ring 5 in said bore, and a ball in said spacer sleeve 00- operating with said seat ring to provide a. check seal, said seat ring having a seal ring therein providing a seal with the bore.

FRED J. WRIGHT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 439,480 Dahlstrom Oct. 28, 1890 751,333 Obolensku Feb. 2, 1904 Number Number 

